Apparatus for the micrometric tuning of the keyboards and similar instruments with elimination of the wooden support of the pegs and the pegs same

ABSTRACT

A tuning device formed in its entirety of metal for micrometric tuning of pianos or similar instruments which permits elimination of the wooden peg supports and the pegs in pianos and improves the stability of the tuning.

Q United States Patent [1 1 [111 3,777,611 Madonna Dec. 11, 1973 4] APPARATUS FOR THE MICROMETRIC 360,409 4/1887 Berner 84/204 TUNING OF THE KEYBOARDS AND 1,026,228 5/1912 Severy et a1. 84/204 SIMILAR INSTRUMENTS WITH 2,917,961 12/1959 Madonna 84/204 ELIMINATION OF THE WOODEN SUPPORT OF THE PEGS AND THE PEGS SAME Inventor: Oronzo Madonna, Via del Mare No.

16, Lecce, Italy Filed: Nov. 26, 1971 Appl. No.: 202,519

Foreign Application Priority Data Dec. 11, 1970 Italy 17109 A/70 US. Cl. 84/204 Int. Cl Gl0c 3/10 Field of Search 84/200-208, 188 I References Cited UNITED STATES PATENTS Meinzolt 84/205 FOREIGN PATENTS OR APPLICATIONS 66,581 2/1893 Germany 84/204 13,036 8/1887 Great Britain... 84/204 572,299 l/l958 Italy 84/204 Primary ExaminerRichard B. Wilkinson Assistant Examiner-John F. Gonzales Att0rneyMichael S. Striker ABSTRACT A tuning device formed in its entirety of metal for micrometric tuning of pianos or similar instruments which permits elimination of the wooden peg supports and the pegs in pianos and improves the stability of the tuning.

4 Claims, 9 Drawing Figures APPARATUS FOR THE MICROMETRIC TUNING OF THE KEYBOARDS AND SIMILAR INSTRUMENTS WITH ELIMINATION OF THE WOODEN SUPPORT OF THE PEGS AND THE PEGS SAME BACKGROUND OF THE INVENTION In pianos and similar instruments many troubles are encountered in connection with wooden supports of the pegs which are used for anchoring and tensioning the piano wires.

These troubles are due to the fact that a wooden sup port is subjected to the influence of changes in the surrounding atmosphere so that the pegs mounted thereon may become loose under the influence of the stressed wires fastened thereto.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a tuning device constructed and supported to overcome the aforementioned disadvantage of tuning devices in which the pegsare supported on a wooden support.

It is a further object of the present invention to provide a tuning device which is composed of a few and relatively simple parts so that the tuning device may be manufactured and assembled at reasonable cost.

It is a further object of the present invention to provide a tuning device in which previously used wooden supports are eliminated and in which an improved stability of the tuning can be obtained.

With these and other objects in view, the tuning device according to the present invention is formed in its entirety only of metal parts and mainly comprises a frame formed from stamped and bent sheet metal in which is mounted a plurality of gear wheels having a hub portion on which the end portion of the string or wire to be tuned may be wound, and a worm cooperating with respective gear wheel for turning the same about its axis to thereby stress the wire or string to the desired degree.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when-read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1A schematically illustrates part of the tuning device, partly in cross-section;

FIG. 1B illustrates a stamped sheet metal part from which the frame of the tuning device is to be formed;

FIG. 2 schematically illustrates a front view of three frames, partly in section and some of which are provided with the aforementioned wheels and worms, as well as an aubtment member on one side of the three frames;

FIGS. 3A and 3B illustrate respectively in crosssection in front view the gear wheel of the device with its shaft;

FIGS. 4A and 4B illustrate the worm screw for operating the gear shown in FIGS. 3A and 3B, respectively in a side view and an end view;

FIGS. 5 and 6 show respectively the framework, preferably formed from cast iron, of a piano in a side view and in a front view.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawing, and more specifically to FIGS. 1A and IE, it will be seen that the tuning device of the present invention comprises a frame formed from a stamped sheet metal of a configuration as shown in FIG. 1B which after stamping is bent along the fold lines 31 indicated in dash lines in FIG. 18 so as to obtain a frame as shown in FIG. IA having a pair of side walls 1 and 3 and a pair of end walls 2 and 4 extending normal thereto. As shown in FIG. 1A the stamped sheet metal part is also provided with a plurality of holes, that is three pairs of holes 5 in the portions of the sheet metal part which forms the walls I and 3, which after bending are aligned with each other, three pairs of holes 6 formed in the portions of the sheet metal which form the walls 2 and 4, which are likewise aligned in pairs when the sheet metal part shown in FIG. 1B is folded to the configuration as shown in FIG.1A, and two additional holes 10 respectively arranged in the region of opposite end portions of the portion 2 of the sheet metal part shown in FIG. 1B and these holes serve to fasten the frame, by means of screws 11 as shown in FIG. 1A to an appropriate support of the piano. FIG. 1A in addition shows an abutment member 9, the purpose of which will be described later on, which is likewise fastened by screw 11 to the aforementioned support.

FIG. 2 illustrates three frames as illustrated in FIG. 1A mounted adjacent to each other so that the side walls 1 and 3 of the middle frame merely abut against corresponding side walls of the two outer frames. It will be also noted from FIG. 2 that the middle frame is slightly shifted in longitudinal direction with respect to the two outer frames so that the holes 5 in the side walls 1 and 3 of the middle frame will not be aligned with the corresponding holes 5 in the two outer frames. FIG. 2 also shows three gear wheels 7 turnably mounted in the middle frame and operating worms 8 cooperating therewith while the left frame is shown empty and in the right frame only a single gear wheel 7 is shown mounted therein. Of course, it is to be understood that each of the frames shown in FIG. 2 may have three gear wheels and cooperating worm screws mounted therein.

The gear wheels 7 are illustrated in further detail in FIGS. 3A and 3B and each of the gear wheels 7 comprises a gear portion formed at its outer periphery with teeth 16 and a cylindrical hub portion 32 of reduced diameter extending coaxially to one side of the gear portion. The gear wheel is formed with a central bore 33 in which a shaft 15 projecting with opposite end portions 14 beyond the gear wheel is located so that the gear wheel may freely turn about this sahft. In addition, the gear wheel is formed in the gear portion thereof with a small diameter bore 12 extending in axial direction therethrough which serves for insertion of an end portion of a piano wire which, during tuning of the latter is to be in part wound about the hub portion 32. The end portions 14 of the shaft of each gear wheel mounted in the respective frame extend through the holes 5 in the side walls 1 and 3 of the frame and due to the displacement of the middle frame in longitudinal direction, the shafts 15 are prevented from movement in axial direction. An abutment member 9 mounted to the left of the leftmost frame shown in FIG. 2 serves also the purpose of preventing the shafts of any gear wheels mounted in this frame from moving towards the left.

The worm screw 8 for turning each of the gear wheels 7 about its axis is illustrated in detail in FIGS. 4A and 4B. As shown in these Figures each of the worm screws 8 comprises two cylindrical portions 17 and 19 which are adapted to be located in corresponding holes 6 of the frame and a helical screw portion 18 between the two cylindrical portions. A portion 20 of noncylindrical cross-section, preferably of a squre crosssection, 21 as shown in FIG. 48 projects to the right, as viewed in FIG. 4A of the cylindrical portion 19 and the portion of square cross section is adapted to be engaged by a corresponding wrench for turning the worm screw 8 about its axis. It is to be understood that the gear teeth 16 of the gear wheel 7 are of a configuration to be properly meshed with the threaded portion 18 of the worm screw.

FIG. shows part of a metal plate 21 of a piano formed with a key rib 23 over which the piano wires are strung and laterally over the rib 23 a window 27 which is bridged by a metal plate 25 fastened to the main plate 22 as screws 26 or the like. The metal plate 25 serves to mount thereon a plurality of frames of the tuning device as illustrated in FIG. 2 which evidently greatly facilitates the assembly of the tuning devices on the piano plate since the tuning devices may be mounted on the plate 25 outside the piano and the plate 25 may be then connected to the plate 22 with the tuning devices mounted thereon. FIG. 5 also shows a reinforcing rib 24 opposite the key rib 23, and the plate 25 may abut with one edge thereof against this rib 24. FIG. 6 scher natically illustrates a piano plate 28 formed with three windows 29.

The tuning device according to the present invention may be manufactured and assembled in an exceedingly simple manner. After stamping a sheet metal to the configuration as shown in FIG. 18 with the plurality of holes 5, 6 and formed therein the sheet metal part is bent along the bent lines 31 to a frame as shown in FIG. 1A and thereafter the wheels 7 are placed into this frame with the bore in each wheel aligned with the holes 5 and then the shaft is placed in the bore of each wheel so that the wheel is turnably mounted in the frame. Subsequently thereto the worm screw 8 is pushed with a cylindrical end portion 17 leading through a corresponding hole 6 formed in the wall portion 4 and during further movement of the worm screw 8 in axial direction the threaded portion 18 thereof will become engaged with the teeth 16 of the corresponding wheel while the latter may freely turn about its axis until the end portion 17 will be lodged in the corresponding hole 6 formed in the wall portion 2. The piano wire end portion is then passed through the small bore 12 of the respective gear wheel and then bent to engage the peripheral surface of the hub portion 32 of the gear wheel. Subsequently, before the last-mentioned operation, the frames and abutment members 9 are connected by screws 11 preferably to the plate shown in FIG. 5 and the latter is then connected by screws 26 I to the main piano plate 22. By subsequently turning the worm screw 8 cooperating with the respective wheel 7, the end portion of the wire may be wound to a greater or lesser degree about the hub portion 32 of the respective gear wheel so as to tune the piano wire 34.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of tuning devices differing from the types described above.

While the invention has been illustrated and described as embodied in a tuning device formed from metal for pianos or similar instruments, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

I claim:

1. A tuning device for micrometrically tuning pianos or similar instruments comprising a support; a plurality of elongated sheet metal frames on said support and having each a pair of side walls and a pair of end walls extending transverse to said side walls and provided in each of said side walls and end walls with a plurality of holes rspectively aligned in pairs with each other; a plurality of gear wheels located between said side walls of each frame respectively aligned with corresponding holes in said side walls, each of said gear wheels having a toothed portion and a coaxial cylindrical hub portion of a diameter smaller than the toothed portion for winding an end portion of a piano wire thereon, a central bore extending in axial direction through said portions, and means for securing the end of said end portion of the piano wire to said gear wheel; a pluraltiy of shafts, one for each gear wheel, and each extending through the central bore of the respective wheel and with opposite end portions respectively into aligned holes in said side walls to thus turnably mount the respective gear wheel; a pluraltiy of worm screws, one for each gear wheel, respectively mounted in aligned holes of said end walls and meshing with the toothed portions of the respective gear wheels, each of said worm screws having a pair of cylindrical portions located in corresponding holes of said end walls, a portion provided with a helical screw thread between said cylindrical portions, and an end portion of non-circular crosssection projecting in axial direction beyond one of said cylindrical portions; and means mounting said pluraltiy of sheet metal frames on said support in side-by-side relationship with adjacent frames displaced from each other in a direction substantially normal to said shafts so as to prevent said shafts in each frame to move in longitudinal direction.

2. A tuning device as set forth in claim 1, wherein said cylindrical portions have equal diameters and the cross-sections of the other portions of said worm screw do not exceed that of said cylindrical portions.

3. A tuning device as set forth in claim 1, and including an abutment member mounted on said support and extending along that side wall of the outermost frame which faces away from the frame adjacent said outermost frames.

4. A tuning device as set forth in claim 1, wherein said support comprises a planar metal plate adapted to be mounted on the main plate of a piano. 

1. A tuning device for micrometrically tuning pianos or similar instruments comprising a support; a plurality of elongated sheet metal frames on said support and having each a pair of side walls anD a pair of end walls extending transverse to said side walls and provided in each of said side walls and end walls with a plurality of holes rspectively aligned in pairs with each other; a plurality of gear wheels located between said side walls of each frame respectively aligned with corresponding holes in said side walls, each of said gear wheels having a toothed portion and a coaxial cylindrical hub portion of a diameter smaller than the toothed portion for winding an end portion of a piano wire thereon, a central bore extending in axial direction through said portions, and means for securing the end of said end portion of the piano wire to said gear wheel; a pluraltiy of shafts, one for each gear wheel, and each extending through the central bore of the respective wheel and with opposite end portions respectively into aligned holes in said side walls to thus turnably mount the respective gear wheel; a pluraltiy of worm screws, one for each gear wheel, respectively mounted in aligned holes of said end walls and meshing with the toothed portions of the respective gear wheels, each of said worm screws having a pair of cylindrical portions located in corresponding holes of said end walls, a portion provided with a helical screw thread between said cylindrical portions, and an end portion of non-circular cross-section projecting in axial direction beyond one of said cylindrical portions; and means mounting said pluraltiy of sheet metal frames on said support in side-by-side relationship with adjacent frames displaced from each other in a direction substantially normal to said shafts so as to prevent said shafts in each frame to move in longitudinal direction.
 2. A tuning device as set forth in claim 1, wherein said cylindrical portions have equal diameters and the cross-sections of the other portions of said worm screw do not exceed that of said cylindrical portions.
 3. A tuning device as set forth in claim 1, and including an abutment member mounted on said support and extending along that side wall of the outermost frame which faces away from the frame adjacent said outermost frames.
 4. A tuning device as set forth in claim 1, wherein said support comprises a planar metal plate adapted to be mounted on the main plate of a piano. 